Adult Population In Norway Research Articles

Historical trends in daily smoking and quitting by relationship status in Norway, 1973-2022.

This study aims to investigate trends in self-reported daily smoking and quitting by relationship status in 1973-2022. Repeated and representative cross-sectional tobacco surveys of the adult population in Norway were analysed in the age group 25-74 years. Logistic regression was used to estimate the adjusted predicted probability of daily smoking and former smoking for persons in a formalised relationship (married or cohabitant) and persons not in a formalised relationship. Since the 1970s, the decline in daily smoking has been present for men regardless of relationship status, but with more smoking among men not in a relationship from the 2000s onward. For women not in a relationship, daily smoking increased among those not in a relationship from the mid-1980s, surpassing the smoking rate among men in a relationship. From the 1990s, daily smoking was higher in women not in a relationship compared with women in a relationship. In the past decade (2013-2022), the adjusted odds ratio of daily smoking was 0.49 for people in a relationship compared with those not in a relationship. Downward trends in daily smoking have been substantial the past 50 years, but differences by relationship status persist. Continued monitoring of smoking behaviour at the population level is crucial to uncover which demographic groups are lagging in the last phase of the tobacco epidemic.

Patterns of physical activity over 34 years in a large sample of adults: The HUNT study, Norway.

To examine physical activity patterns over 34 years in a representative adult population in Norway. Longitudinal data were obtained from the Helseundersøkelsen i Trøndelag (HUNT) study, performed in 1984-1986 (HUNT1), 2006-2008 (HUNT3) and 2017-2019 (HUNT4). There were a total 123,005 participants across all four studies. Physical activity patterns over time are described, in relation to age, gender and body mass index (BMI). Multiple imputation was used to handle missing data. The proportion of adults estimated (using a proxy measure) as being physically active 1 h or more per week increased from 32% in 1984-1986 (HUNT1) to 64% in 2017-2019 (HUNT4). The most frequent pattern was being inactive at HUNT1, becoming active at HUNT3 and staying active (until HUNT4). From HUNT3 to HUNT4, the most frequent pattern was being active at both time points. The adults >50 years old had a similar physical activity pattern from HUNT3 to HUNT4 and were more active than those >50 years. During the period, men were more active than woman, but difference was reduced over time. Both for persons being underweight (BMI ⩽ 18.5) or obese (BMI > 30), the proportion being active at multiple time points was lower than for persons at normal weight. The data indicate a noticeable increase in being physically active for 1 h or more per week during the 34-year study period. Relatively stable patterns of physical activity were identified, with some variations according to age, gender and BMI.

Estimated vaccine effectiveness against SARS-CoV-2 Delta and Omicron infections among health care workers and the general adult population in Norway, August 2021 – January 2022

BackgroundHealth care workers (HCW) have a higher exposure to SARS-CoV-2 virus than other professionals and to protect both HCW and patients, HCW have been prioritized for vaccination against SARS-CoV-2 in many countries. Estimating the COVID-19 vaccine effectiveness among HCW is important to provide recommendations to protect risk groups. MethodsWe estimated vaccine effectiveness against SARS-CoV-2 infections using Cox proportional hazard models among HCW with comparisons in the general population, from 1 August 2021 to 28 January 2022. Vaccine status is specified as a time-varying covariate and all models incorporated explicit time and were adjusted for age, sex, comorbidities, county of residence, country of birth, and living conditions. Data from the adult Norwegian population (aged 18–67 years) and HCW workplace data (as registered 1 January 2021) were collated from the National Preparedness Register for COVID-19 (Beredt C19). ResultsVaccine effectiveness was higher for Delta than for the Omicron variant in HCW (71 % compared to 19 %) as well as in non-HCW (69 % compared to −32 %). For the Omicron variant a 3rd dose provides significantly better protection against infection than 2 doses in both HCW (33 %) and non-HCW (10 %). Further, HCW seem to have better vaccine effectiveness than non-HCW for the Omicron, but not for the Delta variant. ConclusionsVaccine effectiveness were comparable between HCW and non-HCW for the delta variant, but significantly higher in HCW than non-HCW for the omicron variant. Both HCW and non-HCW got increased protection from a third dose.

Oral health and use of dental services in different stages of adulthood in Norway: a cross sectional study

BackgroundSocioeconomic status and oral health care habits may change throughout adult life. This calls for age-stratified analyses of oral health in the adult population to uncover differences that could be of importance for organizing adequate oral health care services. The aim of the present study was to describe self-reported oral health in different age groups in a general adult population in Norway, and to explore associations between self-reported oral health and age groups, sociodemographic factors, use of dental services, number of teeth and dental caries.MethodsWe used data from a cross-sectional study of almost 2000 Norwegian adults, 20–79 years old. The study included both a structured questionnaire and a clinical examination to assess sociodemographic variables, use of dental services, self-reported oral and general health as well as dental caries and number of teeth. For analysis, the participants were divided into three age groups: young adults (20–29 years), middle-aged adults (30–59 years), and senior adults (60 years and older). Differences among groups were analyzed by cross-tabulation, and logistic regression analyses were used to assess associations between variables.ResultsForty-eight percent of the participants rated their oral health as good. Almost half of the participants had at least one carious tooth, with the highest caries prevalence among the young adults. To be caries free was strongly associated with reporting good oral health among the young and middle-aged adults. One third of the senior adults had fewer than 20 teeth, which was associated with reporting moderate or poor oral health. Less than half of the young adults reported regular use of dental services, and 40% of them had postponed dental visits for financial reasons during the past 2 years. Regardless of age group, having to postpone dental visits for financial reasons or having poor-to-moderate general health were associated with high odds for reporting moderate or poor oral health.ConclusionsThat there were important age-group differences in self-reported and clinical measures of oral health and in the use of dental health services demonstrates the importance of age-stratified analyses in oral health research. Many adults, especially among the young, faced financial barriers for receiving dental health services, which was associated with poorer self-reported oral health. This argues for a need to revisit the financing of oral health care for adults in Norway.

Non-prescription purchase of antibiotics during travel abroad among a general adult population in Norway: Findings from the seventh Tromsø Study.

BackgroundNon-prescription purchase of antibiotics is undesirable and has not recently been investigated in a representative population in a high-income low-use country during travel abroad. This study examined self-reported prevalence of antibiotic purchase abroad with and without prescription among participants reporting international travel in a general adult population in Norway, and the associations with socio-demographic, lifestyle and health factors.MethodsWe analysed questionnaire-data from 19995 participants (10470 women) ≥40 years in the population-based Tromsø Study 7, 2015–2016. Data from the Norwegian Prescription Database were used to examine antibiotic use in Norway. We calculated adjusted odds ratios (AOR) for “travel abroad”, “any antibiotic purchase abroad”, and “antibiotic purchase abroad with” and “without prescription” using multivariable logistic regression.ResultsOver half (55.0%, 95%CI 54.3–55.7%) participants reported travel abroad of >1 week duration in the past year. Travelers were more likely than non-travelers to be women (AOR = 2.02, 95%CI 1.42–2.88%) and report high education/income, childhood mostly lived abroad, healthy lifestyle, and good/excellent self-rated health. In total, 17904 travel episodes to 148 countries were reported. Altogether, 3.7% (95% CI 3.4%-4.1%) of travelers had purchased antibiotic abroad in the past year. Non-prescription purchase (1.5%, 95% CI 1.3–1.7) was associated with younger age, being female (AOR 1.41, 1.0–1.97), number of travels (reference: one episode, two: AOR = 1.82, 1.25–2.67, three: 2.60, 1.58–4.28, four: 3.10, 1.40–6.36 and ≥five: 4.70, 2.30–9.62), occurrences of diarrhoea (one: 2.42, 1.50–3.93 and ≥two: 3.08, 1.29–7.35), and antibiotic use in Norway in the past year (1.84, 1.29–2.62), whereas purchase with prescription (2.4%, 2.1–2.7) was associated with low income, growing-up abroad, recent hospital admission, additionally including number of travels/diarrhoea, and antibiotic use in Norway. Thailand (10.7%, 95% CI 7.8–14.3), Turkey (5.5%, 3.8–7.8) and Spain (3.6%, 3.0–4.3) were the countries most commonly associated with any antibiotic purchase. About two in five travelers who bought antibiotics in Thailand had done so without prescription, three in five in Turkey, and less than one in three in Spain.ConclusionOverall, a small proportion of travelers had bought antibiotics abroad in the past year. Low prevalence of non-prescription purchase may be explained by awareness of the risks associated with self-medication, cultural views, unawareness of the non-prescription availability, and/or few infections. Divergent predictors for purchase abroad with versus without prescription may suggest different reasons for these practices.

StudentKost: a cross-sectional study assessing college students' diets: reason for concern?

College students constitute a significant proportion of the young adult population in Norway. They are in their reproductive years, which is of interest regarding diet and preconception health. Our objective was to assess young college students' diet and nutrient intake in relation to national dietary recommendations and assess the probability of inadequate micronutrient intake for both genders using the Nordic Nutrition Recommendations, and also to evaluate its consequences on preconception health and create a groundwork for future interventions on this group. At the University of Agder (UiA), we enrolled 622 students aged 18-40 years for a cross-sectional study of student's diet, StudentKost. The students completed a food frequency questionnaire, including questions of supplement use, over the past 4 weeks. Intake of fruits, vegetables, oily fish, and whole grain was lower than recommended, as were mean intake of folate, iron, and iodine. Our main findings are that students have a somewhat suboptimal diet compared to the Norwegian dietary guidelines. Male students had generally lower diet quality than females. Compared to the Nordic Nutrition Recommendations (NNR), we also saw a relatively high probability of inadequate intake of several micronutrients and a very high probability for some micronutrients in a significant portion of the sample. Public health effort should be directed towards improving students and young adults' diet in general, and interventions towards improving preconception health should be explored. The low participation rate limits the generalizability of our findings. Our findings encourage further investigation into young adults' diet.

The validity of a web-based FFQ assessed by doubly labelled water and multiple 24-h recalls

The aim of this study was to validate the estimated habitual dietary intake from a newly developed web-based FFQ (WebFFQ), for use in an adult population in Norway. In total, ninety-two individuals were recruited. Total energy expenditure (TEE) measured by doubly labelled water was used as the reference method for energy intake (EI) in a subsample of twenty-nine women, and multiple 24-h recalls (24HR) were used as the reference method for the relative validation of macronutrients and food groups in the entire sample. Absolute differences, ratios, crude and deattenuated correlations, cross-classifications, Bland-Altman plot and plots between misreporting of EI (EI-TEE) and the relative misreporting of food groups (WebFFQ-24HR) were used to assess the validity. Results showed that EI on group level was not significantly different from TEE measured by doubly labelled water (0·7 MJ/d), but ranking abilities were poor (r -0·18). The relative validation showed an overestimation for the majority of the variables using absolute intakes, especially for the food groups 'vegetables' and 'fish and shellfish', but an improved agreement between the test and reference tool was observed for energy adjusted intakes. Deattenuated correlation coefficients were between 0·22 and 0·89, and low levels of grossly misclassified individuals (0-3 %) were observed for the majority of the energy adjusted variables for macronutrients and food groups. In conclusion, energy estimates from the WebFFQ should be used with caution, but the estimated absolute intakes on group level and ranking abilities seem acceptable for macronutrients and most food groups.

Subjective health complaints and illness perception amongst adults with Joint Hypermobility Syndrome/Ehlers–Danlos Syndrome-HypermobilityType – a cross-sectional study

Objective: To investigate the prevalence and severity of subjective health complaints and describe illness perception in a population of Joint Hypermobility Syndrome or Ehlers–Danlos Syndrome-Hypermobile Type.Method: This study was a postal survey with a questionnaire battery on demographic data, subjective health complaints inventory, and illness perception. A total of 110 individuals diagnosed with Joint Hypermobility Syndrome or Ehlers–Danlos Syndrome-Hypermobile Type from two specialized hospitals in Norway were offered participation. Further, 140 gender- and age-matched healthy controls from statistics Norway representing the general population were sent the questionnaire for reference.Results: Overall response rate was 30.4% (n = 76), with 44.5% (n = 49) in Joint Hypermobility Syndrome/Ehlers–Danlos Syndrome-Hypermobile Type and 19.3% (n = 27) in controls. Subjective health complaints were significantly higher in Joint Hypermobility Syndrome/Ehlers–Danlos Syndrome-Hypermobile Type - than in the controls (32.06 vs. 11.08; p < 0.001). Further the brief illness perception questionnaire indicated that the adults with Joint Hypermobility Syndrome/Ehlers–Danlos Syndrome-Hypermobile Type had low understanding of their illness and symptoms (understanding, mean: 3.93, SD 2.88), and reported to have moderate personal and treatment control over their illness.Conclusion: Adults with Joint Hypermobility Syndrome/Ehlers–Danlos Syndrome-Hypermobile Type reported higher frequency and severity of subjective health complaints than the matched controls from the general adult population in Norway. Furthermore, Joint Hypermobility Syndrome/Ehlers–Danlos Syndrome-Hypermobile Type reported low understanding of their illness and associated symptoms, and moderate belief that their illness can be kept under control through self-management or treatment. This may indicate one of the reasons why prognosis for these patients is poor.Implications for rehabilitationAwareness of the complexity of the subjective health complaints and inquiry into illness perception could contribute with valuable information about these patients’ perceptions of their condition. Such information could in its turn be of value for clinicians as they work towards facilitating a more holistic treatment approach, for example patient education and cognitive behavioural therapy.

Predictors of Gaming Behavior among Military Peacekeepers – Exploring the Role of Boredom and Loneliness in Relation to Gaming Problems

Abstract The aim of the current study was to explore gaming problems in post-deployment veterans and to investigate whether boredom and loneliness can predict levels of gaming problems. The general well-being of veterans post their deployments to war zones is linked to an array of negative health consequences, and veterans may be at risk for developing gaming problems after homecomings. Problems that may be related to engagement in gaming include coping with negative emotions, such as boredom and loneliness, which are often faced by homecoming veterans as well. The sample in this study comprised Afghanistan veterans (N = 246), with a mean age of 37.5 years (standard deviation = 9.6 years), and 8.8% of the veterans showed symptoms indicative of problem gaming. This is not higher than that found in the general adult population in Norway. Logistic regression analyses showed that boredom proneness (lack of internal stimulation) and enhancement motivation were independent significant predictors of gaming problems, after controlling for age, gender, coping motivation, social motivation, anxiety, depression, loneliness, lack of external stimulation, hazardous drinking, and combat exposure. These factors accounted for as much as 65.8% of the variance in gaming problem status. We conclude that veterans who are highly motivated by enhancement motives and score low on lack of internal stimulation may be prone to developing gaming problems.

Long-term Use of Z-Hypnotics and Co-medication with Benzodiazepines and Opioids.

Benzodiazepine-like drugs (z-hypnotics) are the most commonly used drugs for treatment of insomnia in Norway. Z-hypnotics are recommended for short-term treatment not exceeding 4 weeks. We aimed to study the use of z-hypnotics in the adult population in Norway with focus on recurrent use in new users, treatment intensity and co-medication with benzodiazepines and opioids in long-term users. Data were obtained from the Norwegian Prescription Database. New users in 2009 were followed through 2013. Recurrent z-hypnotic use was defined as new fillings at least once in each of the four 365-day follow-up periods. Age groups of 18-39, 40-64 and 65+ years were analysed separately for men and women. In 2013, 354,571 (8.9%) of the population filled at least one prescription of z-hypnotics and the prevalence was relatively stable over time. Among the 92,911 new users of z-hypnotics in 2009, 13,996 (16.8%) received z-hypnotics all four 365-day periods of follow-up. In these long-term recurrent users, the treatment intensity was high already the second year, with mean annual amounts of 199 and 169 DDDs per patient in men and women, respectively. The interquartile differences were greatest in the youngest age group. 27.9% of the long-term recurrent users of z-hypnotics used benzodiazepines the fourth year and 33.9% used opioids. The proportions with co-medication increased with level of z-hypnotic treatment intensity. Overall, many z-hypnotic users had medicines dispensed for longer periods than recommended, and co-medications with drugs that may reinforce the central depressing and intoxicating effects were common.

Social Preferences in the Lab: A Comparison of Students and a Representative Population

AbstractWe report from a lab experiment conducted with a sample of participants that is nationally representative for the adult population in Norway and two student samples (economics students and non‐economics students). The participants make choices both in a dictator game (a non‐strategic environment) and in a generalized trust game (a strategic environment). We find that the representative sample differs fundamentally from the student samples, both in the relative importance assigned to different moral motives (efficiency, equity, and reciprocity) and in the level of selfish behavior. It is also interesting to note that the gender effects observed in the student samples do not correspond to the gender effects observed in representative sample. Finally, whereas economics students behave less pro‐socially than non‐economics students, the two student groups are similar in the relative importance they assign to different moral motives.

Hot cognition in agricultural policy preferences in Norway?

The paper tests the hypothesis that cultural and social background is far more influential to form preferences about policy than the level of fact-based knowledge a person possesses. The data for the case study stem from a web-based survey among a representative sample of the adult population in Norway. The degree of knowledge of agriculture in this paper is operationalized through questions on five key characteristics of Norwegian agriculture that frequently arise in the public discussion. The results show that the amount of fact-based knowledge of agriculture to a very little extent explains differences within the sample. The cultural background of respondents is much more suited to explain agricultural policy preferences. Knowledge, however, shifts the attention from food price issues towards the delivery of public goods. The results allow us to hint at hot cognition as a possible explanation for such findings.

A Norwegian Study of the Suitability of Hair Samples in Epidemiological Research of Alcohol, Nicotine and Drug Use

A feasibility study was performed to examine the effectiveness of hair testing in determining the prevalence of drug use in a young adult population. The study included 200 randomly selected young adults in Norway. It was designed to make the collection, preparation and analysis of the samples as little resource demaning as possible. Full anonymity was provided for the participants. In total, 23.5% of the samples were positive for one or more substances (14.5%, excluding the nicotine metabolite cotinine). Of the samples, 5% were positive for at least one illegal drug, 9.5% for a medicinal drug, 11.5% for cotinine and 2.5% for the alcohol metabolite ethyl glucuronide. The preliminary findings suggest that the study protocol used to collect and analyze the samples was unable to produce results that could be generalized to the young adult population in Norway. Analysis of hair samples may underestimate the use of cannabis, alcohol, amphetamine and methamphetamine. It may, however, be done to estimate cocaine and general drug use if a sample-collection procedure different from that described in our study is used and includes information about hair length, sample length, length from the scalp, cosmetic treatment, washing and whether the samples always get washed/decontaminated prior to analysis.

Trends in overweight and obesity over 22 years in a large adult population: the HUNT Study, Norway.

Some reports indicate that the obesity epidemic may be slowing down or halting. We followed body mass index (BMI) and waist circumference (WC) in a large adult population in Norway (n = 90 000) from 1984–1986 (HUNT1) through 1995–1997 (HUNT2) to 2006–2008 (HUNT3) to study whether this is occurring in Norway. Height and weight were measured with standardized and identical methods in all three surveys; WC was also measured in HUNT2 and HUNT3. In the three surveys, mean BMI increased from 25.3 to 26.5 and 27.5 kg m−2 in men and from 25.1 to 26.2 and 26.9 kg m−2 in women. Increase in prevalence of obesity (BMI ≥ 30 kg m−2) was greater in men (from 7.7 to 14.4 and 22.1%) compared with women (from 13.3 to 18.3 and 23.1%). In contrast, women had a greater increase in abdominal obesity (WC ≥ 102 cm for men and WC ≥ 88 cm for women). There was a continuous shift in the distribution curve of BMI and WC to the right, demonstrating that the increase in body weight was occurring in all weight groups, but the increase of obesity was greatest in the youngest age groups. Our data showed no signs of a halt in the increase of obesity in this representative Norwegian population.

Incidence of Hospital-Admitted Severe Traumatic Brain Injury and In-Hospital Fatality in Norway: A National Cohort Study

Aims: The aims of this study were to assess the incidence of hospital-admitted severe traumatic brain injury (TBI) in the adult population in Norway, and to determine whether there were differences in the epidemiological characteristics of severe TBI between rural and urban regions. Methods: A prospective population-based study on adults with severe TBI admitted to the Norwegian Trauma Referral Centres during the 2-year period (2009–2010). The electronic patient register was searched weekly for ICD-10 diagnoses of intracranial injuries (S06.0–S06.9) to identify patients. Severe TBI was defined as lowest unsedated Glasgow Coma Scale Score ≤8 during the first 24 h after injury. Results: The annual age-adjusted incidence was estimated at 5.2/100,000 in 2009 and 4.1/100,000 in 2010. The highest frequency of hospitalized patients was found among the youngest and the oldest age groups. The most common causes of injury were falls and transport accidents. The highest in-hospital case-fatality rate was found among the oldest patients. There were consistent epidemiological characteristics of severe TBI from both rural and urban regions. Conclusions: The incidence of hospital-admitted patients with severe TBI in this national study supports the declining incidence of TBI reported internationally. No major differences were found in epidemiological characteristics between the urban and rural parts of Norway.

Demand for and utilization of dental services according to household income in the adult population in Norway

The aim of this study was to describe the effect of income on demand and utilization of dental services according to household income in the adult population. The data were collected using a questionnaire, which was sent to a random sample of Norwegians aged 20 years or older living at home, 1861 persons in total. Demand was measured according to whether the person had been to the dentist during the last year. Utilization was measured as expenditure for dental treatment for those who had been to the dentist during the last year. The independent variables were the respondents' household income, age, gender, education, dental status and the mean fee for a dental consultation in the municipality. In the first stage, we carried out a logistic regression analysis of the log odds of having demanded dental services during the last year. In the second stage, we carried out a multiple regression analysis of expenditure for dental treatment for those who had been to the dentist during the last year. Altogether, 80% of the respondents had been to the dentist during the last year. Demand during the last year varied most according to dental status. There was little difference between men and women. The results of the logistic regression showed that the probability of having been to the dentist was 0.82 for those with a household income of €25 000 and 0.85 for those with a household income of €100 000. Mean expenditure for dental treatment was €355. There was no statistically significant relationship between household income and expenditure for dental treatment. Differences in demand for dental services according to household income are small, and there are no differences in utilization according to income. The findings are interesting, because in a population in which people have to pay almost all the costs for dental treatment themselves, one would expect the income differences in demand and utilization to be greater.

Efficiency, Equality and Reciprocity in Social Preferences: A Comparison of Students and a Representative Population.

The debate between Engelmann and Strobel (2004, 2006) and Fehr, Naef, and Schmidt (2006) highlights the important question of the extent to which lab experiments on student populations can serve to identify the motivational forces present in society at large. We address this question by comparing the lab behavior of a student group and a non-student group, where the non-student group on all observable factors is almost identical to the representative adult population in Norway. All participants take part in exactly the same lab experiment. Our study shows that students may not be informative of the role of social preferences in the broader population. We find that the representative participants differ fundamentally from students both in their level of selfishness and in the relative importance assigned to different moral motives. It is also interesting to note that while we find no significant gender differences among the students, males and females in the representative group differ fundamentally in their moral motivation.

International and Domestic Altruism: A Study Among the Adult Population in Norway

Instead of targeting charity to countries where the human needs are most precarious, donors tend to direct their helping to victims within their own country. Despite being important for human welfare, the question why it is so has heretofore not been raised scientifically. In this survey study (N = 3849 respondents) a suggested distinction between international and domestic altruism was validated by examining to which extent the 2 concepts showed differing patterns of associations with a range of relevant variables. When controlling for demography, international orientation, trust in people, and less xenophobia predicted international altruism, while patriotism and fear predicted domestic altruism. Research on how national boundaries stem altruism should be intensified and refined.

Oral health equality during 30 years in Norway

To study the relationship between income and edentulousness and having a functional dentition from 1975 to 2002, and to examine whether or not the findings can be characterized as a social gradient. Four datasets were collected by personal interviews and precoded questionnaires by Statistics Norway in 1975, 1985, 1995 and 2002. The datasets were representative of the non-institutionalized adult population in Norway. Each year, the sampled persons were distributed into five income quintiles. Four effects were examined of the relationship between income quintiles and edentulousness and functional dentition (1) the absolute equality effect, (2) the period effect, (3) the relative equality effect, and (4) the gradient effect. The main finding is that in absolute terms oral health is more equally distributed in 2002 than in 1975, and the lowest income groups benefited the most in oral health. Among the elderly, however, having a functional dentition was less equally distributed in 2002. The relative differences increased for the oldest for each new birth cohort; thus, the chances of being edentulous was 7.5 times higher in the lowest income group versus the highest group in 2002, whereas the chances were only two times higher in 1972. Having lost all natural teeth was infrequent in 2002, and inequality wiped out in the population below > or = 60 years. A small social gradient was still in 2002. The condition of edentulousness is a result of accumulated incidences of dental diseases and fragmented access to dental care. Economic barriers and unavailability of dental care postponed necessary restorative dental care and resulted in more drastic treatment solutions previously especially in the rural areas in Norway.

Is birth history the key to highly educated women's higher breast cancer mortality? A follow‐up study of 500,000 women aged 35–54

A positive relationship has been found between high levels of education and breast cancer mortality. The aim of our study is to determine if the educational gradient in breast cancer mortality persists after adjustment for reproductive history. Register data including the total adult population in Norway were used. A total of 512,353 Norwegian women 35-54 years of age at the Norwegian Census in 1990 were followed with respect to breast cancer deaths until December 31, 2001. The analysis included 2,052 breast cancer deaths in 5.6 million person years. Educational differences in breast cancer mortality were analysed using Cox regression. The age adjusted relative risk of dying from breast cancer for women with >12 years of education compared to women with <10 years was 1.25 (95% confidence limits [CI] = 1.10-1.41). Adjustment for age at first birth with nulliparous as reference category reduced this difference to 1.08 (95% CI = 0.95-1.23). For parous women, age at first birth explained all the educational difference in breast cancer mortality. Among nulliparous women there was a larger positive educational gradient in breast cancer mortality than among parous women (relative risk [RR] = 1.57, 95% CI = 1.15-2.13), indicating that there were differences in other confounders than birth history among the childless.